﻿<p>This objectified relationship between a distribution flow element occurrence and one-to-many control element occurrences indicates that the control element(s) sense or control some aspect of the flow element. It is applied to <em>IfcDistributionFlowElement</em> and <em>IfcDistributionControlElement</em>.</p>

<p>This relationship may be used to indicate an operational relationship such as an actuator operating a valve, damper, or switch.  It may also be used to indicate a sensing relationship such as a sensor detecting conditions of fluid flow.</p>

<p>This relationship implies a sensing or controlling relationship; if elements are merely connected without any control relationship, then <em>IfcRelConnectsElements</em> should be used.</p>

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HISTORY&nbsp; New entity in IFC2x.<br>
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